The prior art is documented with examples of heat dissipation, or heat sinking, assemblies for use with a firearm barrel. As is known, repeated discharge of rounds in either of semi-automatic or automatic firing modes results in rapid heating of the barrel to an excessive degree, resulting in the requirement to provide for cooling of the barrel to prevent damage or a misfiring condition.
A first example is disclosed in the heat sink rail system of Lee, US 2014/0082990 which teaches passing air through fins configured in the rail system, such further adapted for mounting other accessories. The fins can be configured either axially along the barrel or in either of inwardly or outwardly extending fashion relative to the rail system.
A further example is shown in Samson, U.S. Pat. No. 8,448,367 which teaches a modular fore-end rail assembly for mounting onto a firearm which includes a hand guard and a bushing element that combines with an end portion of the hand guard to encircle a standard barrel nut. The material construction facilitates heat transfer from the barrel nut to the hand guard at an adjusted rate such that rapid changing of the bushing elements changes the heat rate of the hand guard.
Other relevant examples include each of the firearm heat sink of Muirhead, U.S. Pat. No. 6,508,159, the heat removal system of Larson, U.S. Pat. No. 6,827,130, the fin-type heat exchanger of Price, WO 84/04432, the universal barrel nut for a firearm of Mueller, U.S. Pat. No. 8,726,559, and the heat exchanger barrel nut of Davies et al., U.S. Pat. No. 7,464,496.